E-cigarettes do not have dangerous chemicals, such as tar and arsenic, that are found in tobacco cigarettes.
Photograph: Yui Mok/PA

Experimentation with e-cigarettes is rising among 11- to 18-year-olds in Britain but is most common among those who already smoke or who have done in the past, according to anti-tobacco group Action on Smoking and Health (Ash).

It says results from its third annual online survey of young people’s attitudes to e-cigarettes suggest that it is “unlikely” they are currently acting as a gateway to tobacco.

Although 10% of nearly 2,300 surveyed for Ash by YouGov in March said they had tried e-cigarettes “once or twice”, up from 4% two years ago, regular use remained rare.

Only 2.4% said they used them at least once a month and almost all were young people who said they had been, or were still, regular tobacco smokers. The increases in use have happened as regular tobacco smoking by 11- to 15-year-olds has dropped to a low of 3%.

Ash is concerned, however, that a growing proportion of young people believe vaping is as harmful as smoking cigarettes – a figure that has increased from 11% in 2013 to 21% this year, even if most correctly thought e-cigarettes less harmful.

The finding comes just days after the Royal Society for Public Health called for a public education campaign that might help smokers not yet ready to give up their nicotine habit switch to e-cigarettes, since these did not also have the more dangerous chemicals, such as tar and arsenic, found in tobacco cigarettes.

Authors of the journal report, though it only covers the first two surveys, also express concerns at the increasing proportion of young people perceiving e-cigarettes to be as hazardous as tobacco ones. This, it warns, may reduce numbers of young people “willing to try and/or use what is evidently a much less hazardous source of nicotine”.

They also however say young people are “still relatively inexperienced” in the use of e-cigarettes and recognise concerns over their attraction to young people. Close surveillance must continue on any relationship between e-cigarette use and that of conventional cigarettes, “and the extent to which engagement in one use precedes or replaces the other”.

Hazel Cheeseman, director of policy at Ash, said: “These results should reassure the public that electronic cigarettes are not linked with any rise in young people smoking. Although more young people are trying electronic cigarettes and many more young people are aware of them, this has not led to widespread regular use or an increase in smoking.”

A new law will prohibit their sale to under-18s in England and Wales from 1 October and Scotland is planning to follow suit soon. In Wales, e-cigarette use will also be banned in enclosed public places, as tobacco smoking already is.

Kevin Fenton, national director for health and wellbeing at PHE, said this would “further reduce teenagers access to these products and will reinforce the message that they are intended for adult smokers who want to cut down or stop smoking”.

The Welsh government said: “We are concerned the use of e-cigarettes may re-normalise smoking, especially for a generation who have grown up in a largely smoke-free society.

“We are not alone in our concerns – the World Health Organisation and other international bodies have called for greater regulation of e-cigarettes and 40 other countries have already taken similar steps.”